Taiwan has culled more than 100 birds smuggled from China as the island steps up measures against a deadly strain of avian flu that has killed at least eight people.

According to officials, 109 parrots and pigeons illegally transported from the mainland were seized by the coastguard in the fishing port of Naniliao in northern Hsinchu county. Four men were arrested in connection with the crime.

“This is a sensitive moment. All the birds have been destroyed,” coastguard official Kuo Sen-yao told AFP.

Chinese authorities have reported 24 cases of the H7N9 – a bird flu virus not previously seen in humans – as the reported death toll rose to eight on Tuesday.

While it remains unclear how humans contracted the disease, Taiwan said it would initiate temperature checks at airports on passenger from Jiangsu, Anhui, Shanghai, where infections have been reported.

Shanghai authorities also ordered a wide-scale slaughter of poultry in an effort to contain the spread of the virus, reports the Wall Street Journal. Sales of live pigeons and ducks were banned after authorities discovered H7N9 in samples taken from the birds at three different wholesale markets in the Chinese city.